God bless Google. I was doing some prep work for tomorrow I'll be doing a full mock-up of the Hartford to Southington VPN connection and dug up one of the Nortel ARN routers that sleep in my basement. I need the ARN to stand in for the Internet (yes, one little router will sub for the entire Internet). I bought this ARN on EBay back in '01, used it for a couple of tests, put it on a shelf, and then forgot the administrative password.
I tried every password I could think of.
Then I tried Google.
A search on "ARN password recover" turned up what I needed as the first link: a FAQ page with an article titled "Lost your ARN password?" Hallelujah! A procedure for interrupting the router's self-test and telling it to dump Manager's password. I now have a configured router ready to go, and one less thing to try to cram into tomorrow.